Video Experimental Relacionado
Updated: Jul 11, 2026
10:28
Agrobacterium-Mediated Immature Embryo Transformation of Recalcitrant Maize Inbred Lines Using Morphogenic Genes
Published on: February 14, 2020
Arquitectura teosinte glume 1: Un locus genético que controla un paso clave en la evolución del maíz
Science (New York, N.Y.)
|October 8, 1993
Resumen
El maíz evolucionó a partir de la teosinta, con un cambio clave en los granos expuestos en lugar de los encapsulados. Los investigadores identificaron el gen teosinte glume architecture 1 que controla este rasgo evolutivo crucial.
Área de la Ciencia:
- Genética vegetal Genética vegetal
- Biología evolutiva Biología evolutiva.
- Ciencias agrícolas Ciencias agrícolas.
Sus antecedentes:
- El teosinte, el antepasado del maíz, presenta cáscaras de fruta endurecidas que encierran sus granos, lo que limita la comestibilidad.
- El maíz posee componentes de cáscara de fruta, pero su desarrollo interrumpido da como resultado núcleos expuestos, una divergencia evolutiva crítica.
- Esta transición de los granos encastrados a los expuestos marca un hito significativo en la domesticación y evolución del maíz.
Objetivo del estudio:
- Identificar y caracterizar la base genética para la diferencia morfológica en la cubierta del grano entre el maíz y su progenitor, teosinte.
- Comprender el control genético subyacente a la evolución de los granos expuestos en el maíz.
Principales métodos:
- Cartografía genética del locus de la arquitectura teosinte glume 1 (tga1).
- Análisis comparativo del desarrollo del núcleo en maíz y teosinte.
Principales resultados:
- El locus teosinte glume architecture 1 (tga1) fue identificado como el determinante primario del fenotipo del núcleo encapsulado (teosinte) versus expuesto (maíz).
- El mapeo genético localizó con precisión el locus tga1, proporcionando una base para futuros estudios moleculares y evolutivos.
- El estudio confirmó que el desarrollo interrumpido de los componentes de la cáscara de fruta, regulados por tga1, conduce a granos expuestos en el maíz.
Conclusiones:
- El gen teosinte glume architecture 1 (tga1) juega un papel fundamental en la evolución morfológica del maíz de teosinte.
- Comprender la regulación genética de la cubierta del grano es crucial para la cría de maíz y comprender su historia de domesticación.
- La identificación y el mapeo de tga1 proporcionan información valiosa sobre la arquitectura genética subyacente a las principales transiciones evolutivas en las plantas de cultivo.
Videos de Conceptos Relacionados
02:13Overview of Transposition and Recombination
Transposons make up a significant part of genomes of various organisms. Therefore, it is believed that transposition played a major evolutionary role in speciation by changing genome sizes and modifying gene expression patterns. For example, in bacteria, transposition can lead to conferring antibiotic resistance. Movement of transposable elements within the genetic pool of pathogenic bacteria can aid in transfer of antibiotic-resistant genetic elements. In eukaryotes, transposons can carry out...
02:31Synteny and Evolution
John H. Renwick first coined the term “synteny” in 1971, which refers to the genes present on the same chromosomes, even if they are not genetically linked. The species with common ancestry tend to show conserved syntenic regions. Therefore, the concept of synteny is nowadays used to describe the evolutionary relationship between species.
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral chromosome underwent...
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral chromosome underwent...
01:24Evolution of New Traits in Microbes
Microorganisms evolve rapidly due to their large population sizes and short generation times, often exhibiting measurable changes within days under laboratory conditions. Natural selection acts on standing genetic variation, enabling the retention and amplification of beneficial traits that confer fitness advantages in changing environments.Adaptive Pigment Regulation in RhodobacterIn Rhodobacter, a genus of purple non-sulfur bacteria, light-harvesting pigments such as bacteriochlorophyll and...
02:02Cis-regulatory Sequences
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...
02:57DNA-only Transposons
DNA-only transposons are called autonomous transposons since they code for the enzyme transposase that is required for the transposition mechanism. Insertion of transposons can alter gene functions in multiple ways. They can mutate the gene, alter gene expression by introducing a novel promoter or insulator sequence, introduce new splice sites, and change the mRNA transcripts produced, or remodel chromatin structure.
The donor site from where the transposon is excised is either degraded or...
The donor site from where the transposon is excised is either degraded or...
02:37Gene Duplication and Divergence
The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.